Researchers at the National Institute of Neurological Disorders and Stroke (NINDS) seek patients with stroke for participation
in a study. The study will examine the behavioral consequences of transient inactivation of the ipsilateral cortex on motor
performance of the affected arm in chronic stroke patients with complete and incomplete motor recovery. The results from this
study will provide fundamental information on the role of the ipsilateral cortex in recovery of motor function after chronic
stroke.

Eligible patients include those with single ischemic hemispheric lesions at least 12 months after stroke and with a severe
paresis (below MRC grade 2) of the affected arm initially. An anatomical magnetic resonance imaging (MRI) scan will be acquired
at the National Institutes of Health (NIH) if a recent one (within 6 months) is not available. Healthy normal volunteers who
are willing and able to perform the tasks will also be included in the study, and will receive neurological and physical exams
to ensure their healthy conditions.

A partial list of exclusion criteria includes patients with more than one stroke, bilateral motor impairment, cerebellar or
brainstem lesions, and a history of severe alcohol or drug abuse, psychiatric illness like severe depression, poor motivational
capacity, or severe language disturbances, particularly of receptive nature or with serious cognitive deficits, and those
unable to perform the task (wrist or elbow flexion at least MRC grade 2).

The study will take place at the NIH Clinical Center in Bethesda, MD. All study-related expenses will be paid by the NIH.